Motor-stopping device for telegraph typewriters



Oct-Q23, 1928. 1,688,711

E. W. HEWITT ET AL MOTOR STOPPING DEVICE FOR TELEGRAPH TYPEWRITERS' Filed Feb. 26, 1927 2 Sheets-Sheet 1 Oct. 23, 1928. 1,688,711

- E. w. HEWITT ET AL MOTOR STOPPING DEVICE FOR TELEGRAPH TYPEWRITERS Filed Feb. 26,1927 2 Sheets-Sheet 2 Patented Oct. 23,1928. Y

UNITED .s

ERN UNION TELEGRAPH COMPANY, YORK.

of the motor which drives the operatingmechanism of a printing telegraph machine when no signals have been-'receivedtor a p redetermined period. A further ob ect is ;to prevent the motor from being stopped while the printer is in operation.-

In the accompanying drawings, Figures 1,

2 and .3 are diagrammatic illustrationsrespectively of three diflerent motor stopping devices for accomplishing our purpose; Fig.

4 is an end elevation of the cam mechanism shown in Fig. 2; and Fig. 5 Is an elevation of the timing mechanism of Fig. 3 taken on the line 5-5.

Our motor stopping devlces may be applied to the printing telegraph machines now in use, such for instance, as the telegraph typewriter disclosed In U. S. patent to Edward E. Kleinschmidt, No. 1,567,599, dated December 29, 1925. The driving motor is indicated at 5 and the printer selecting magnet at 6 in each of the forms illustrated. The motor circuit 7, 8 is normally closed at the contacts 9, 9.

In the arrangement motor stopping device consists primarlly ofa toothed sector 10, pivoted at 12 and which is advanced one tooth at a timeby 'a reclprocatingfeed pawl 14, pivoted eccentrlcally on the gear 15. .The gearis driven-very slowly, say four revolutions per minute, by aworm 16 on a shaft 17 which is connected in any suitable manner to be driven rapidly by the motor 5, say four hundred revolutions per minute. In this manner the toothed sector-1s slowly moved aboutits pivot, backward movement being prevented by the dog 18. At each movement of the printing bail to throw a;

' in dotted lines.

type-bar forward into printing position, an

intermediate member-19, connected to the printing bail, is moved downward to disengage the dog 18 from the toothed sector and lift it, together with the pawl 14 suflic1ently to allow the sector to swing back Into its initial position againstthe stop pin 23, as shown After the printing of each letter or charac ter, the printing bail and the member 19 rethe contacts 9, 9

ASSIGNORS' TO THE WEST- OF NEW YO K, N. Y., A CORPORATION OF NEW MOTOR-STOPPING DEYICE rim TELEGRAPH TirrEwnrrERs.

Application filed February'26, 1927. Serial No. 171,328.

turn to normal position, permitting the pawl 14 and dog 18 to drop back into engagement with the teeth of the sector. If no signals are received over the telegraph line 25', the reciprocations of the pawl will swing the sector around until a an'insulatin'g switch button 27, which opens the motor circuit at the contacts 9, 9 and also the short-circuit around the magnet 28 at the contacts 13; 13. This stops the motor and energizes the magnet 28. As the latter attracts its'armature 28?, the sector is given a sudden strong pull which causes the finger 10 to engage the projection 18%, thereby liftmg the dog 18 high enough to cause its outer end to notch in the lower end of the locking member 20 and be locked in this position by the action of the spring 21.

' Although the pawl and dog are held away from the teeth of the' sector, the latter is held by the magnet until the operator at the other end of the hue desires to send a message. The

opening of the line deenergizes the magnet 28 and-allows the sector to swing back to initial position againstthe stop 23, thereby closing to start the motor 5 and the contacts 13, 13 to close the shunt around the magnet. When the printing hail of the L printer is operated to cause the printing of the shoyvn in Fig. 1, the

first letter of the message, the tripping arm J. MAUS, or PATERSON,

r o IcE.

ERNEST W. HEWITT, OF STAMFORD, CONNECTICUT; FRANK NEW JERSEY; AND GEORGE MARX OF NEW YORK, N. Y.,

pin 26 thereon engages or member 19 pushes the dog 18 downwardly untilits outer end moves along the inclined wall of the notch 20= and swin'gsthe member 20 outwardly. enough to permitthedog 18 and the pawl 14 to spring back into engagement with the sector teeth. Thereafter the reciprocating movement of the pawl 14 gradually moves the sector one tooth at a time; but each time the printer bail operates to print a character, the tripping arm.

19 lifts the pawl and dog from the teeth, thus permitting thesectonto swing backto initial position. In this manner the sector is prevented from moving far enough, while'the printer is in operation, to cause the pin 26 to open the switch, contacts. As soon as the transmission ceases the sector will be moved without interruption until the pin 26 opens the switch contacts after predetermined interval and stops the motor.

The arrangementillustrated in Fig. 2 accomplishes the same purpose as the apparatus shown in Fig. '1. In this form of the invention, the pin which opens the switch contacts is carried by a lever 10' and is adually moved'from initial position to switc -operating position by means ,of a cam disk The disk is connected in any suitable manner to be slowly rotated by the motor 5. The

lever arm 10', which carries the switch actuatingjpin 26', is'providedwith a stud projection 30 which rides against the periphery of a cam disk 31 and then enters the cam groove 32, by which it is gradually moved toward the center of the disk.

During the interval when no messa e is transmitted, the lever will be moved rom tracted which movcs the stud out of the full line to dotted line position. At this point in its travel the pin 26' engages the insulating block 27 and opens the pairs of switch contacts 9, 9' and'13, 13', thus stoppin the motor and opening the shunt aroun the magnet 28'. The armature 28 is then at:

observed that the opening of either set of contacts 9, 9 or 9', '9' does not open the motor circuit since they arev connected in parallel. It is necessary to open both sets simultaneousl'y to'break the motor circuit.

tion. This prevents the stopping of the motor while a message is being received by the printer.

A third form of apparatus for carrying out this inventionis illustrated diagrammatically in Figs. 3 and 5. The shaft 17' is connected to the driving motor 5 of the printer in a manner to be driven at say 400 revolutions per minute. Disks 36 and 37 which I carry the switch actuatin pins 26, 26", are

loose on the shafts 38 an which is immediately I 39 and are driven by the gears 34 and through the clutches 41 and 42. The gears are provided with different numbers of teeth. If gear 34 has teeth and gear 35 has 39 teeth, then when the shaft 17 is rotated at 400revolutions per minute, the pins 26 and 26" will engage the respective switch blocks 27 and 27 simultaneously after they have been rotating about four minutes. When this occurs the switch contacts 9, 9 will be open and also the contacts 13,.13'. The opening of the contacts 13, 13' breaks the shunt around magnet 28" the contacts, 9, 9', t ereby openin the cir- In order that the motor shall not be stopped while a message is being received, a device. to interrupt the motion of the timing. mechanism is provided, as in the two forms previously described. Torsion springs 43, 44 sur- Y round the shafts and are connected at one end to the hubs of the disks and at the other end to the stationary bearing posts. 'When the disks are rotated, the sprin s are wound about the shafts and placed un er tension. Each operation of the printing hail of the printer actuates the lever 19 and causes it to move the yokes 45 and 46, sliding the disks and disengaging theclutches 41, 42. The springs then return the disks to initial position.

ratus performs the same function of opening the motor circuit when no message has been received for a predetermined period, but in terrupting the operation of the timing device durin operation'of the printing function.

We claim:

'1. In combination with'a printing telegraph machine having an electric motor to operate the movable parts, of a motor stop-;

ping device comprising an actuating element driven by said motor, timing mechanism operated by said actuating element, a switch 1n the motor circuit operated to open position by said timing mechanism when the latter has operated a predetermined period, and means controlled by the operation of the printing mechanism of the machine to release saidtiming mechanism and permit itto move to initial position. t

2. ,In an organlzation as set forth in claim "1., an electro-magnet connected in the teleenergized and opens cuit 7, and stopping the motor. t willbe s graph line circuit and positioned to hold the timing mechanism in position to maintam the switch in the motor circuit open, a shunt circuit normally short-circuiting said magnet and switch contacts in said shunt circuit, said timing mechanism operating to open said switch contacts simultaneously with the opening of the switch in the motor circuit.

In testimony whereof we afiix our signatures.

ERNEST WV. HEWITT. FRANK J. MAUS. GEORGE MARX.

It will be observed that'each form of appai the reception of a message at' each 

